#include <stdlib.h>
#include <stdio.h>
#include "zbuffer.h"

#define ZCMP(z,zpix) ((ZPOINT)(z) >= (ZPOINT)(zpix))

void
ZB_plot(ZBuffer * zb, ZBufferPoint * p) {
  ZPOINT *pz;
  PIXEL *pp;
  unsigned int zz;
  
  pz = zb->zbuf + (p->y * zb->xsize + p->x);
  pp = (PIXEL *) ((char *) zb->pbuf + zb->linesize * p->y + p->x * PSZB);
  zz = p->z >> ZB_POINT_Z_FRAC_BITS;
  if (ZCMP(zz, *pz)) {
    *pp = RGB_TO_PIXEL(p->r, p->g, p->b);
    *pz = zz;
  }
}

#define INTERP_Z
static void
ZB_line_flat_z(ZBuffer * zb, ZBufferPoint * p1, ZBufferPoint * p2, 
               unsigned int color) {
#include "zline.h"
}

/* line with color interpolation */
#define INTERP_Z
#define INTERP_RGB
static void
ZB_line_interp_z(ZBuffer * zb, ZBufferPoint * p1, ZBufferPoint * p2) {
#include "zline.h"
}

/* no Z interpolation */

static void
ZB_line_flat(ZBuffer * zb, ZBufferPoint * p1, ZBufferPoint * p2, 
             unsigned int color) {
#include "zline.h"
}

#define INTERP_RGB
static void
ZB_line_interp(ZBuffer * zb, ZBufferPoint * p1, ZBufferPoint * p2) {
#include "zline.h"
}

void
ZB_line_z(ZBuffer * zb, ZBufferPoint * p1, ZBufferPoint * p2) {
  unsigned int color1, color2;

  color1 = RGBA_TO_PIXEL(p1->r, p1->g, p1->b, p1->a);
  color2 = RGBA_TO_PIXEL(p2->r, p2->g, p2->b, p2->a);

  /* choose if the line should have its color interpolated or not */
  if (color1 == color2) {
    ZB_line_flat_z(zb, p1, p2, color1);
  } else {
    ZB_line_interp_z(zb, p1, p2);
  }
}

void
ZB_line(ZBuffer * zb, ZBufferPoint * p1, ZBufferPoint * p2) {
  unsigned int color1, color2;

  color1 = RGB_TO_PIXEL(p1->r, p1->g, p1->b);
  color2 = RGB_TO_PIXEL(p2->r, p2->g, p2->b);

  /* choose if the line should have its color interpolated or not */
  if (color1 == color2) {
    ZB_line_flat(zb, p1, p2, color1);
  } else {
    ZB_line_interp(zb, p1, p2);
  }
}
